Replaceable-point excavator tooth



Nov. 6, 1928.

1,690,834 T. RATKowsKl REPLACEABLE POINT EXCAVATOR TOOTH Filed Juli: 25,1927 2 Sheets-Sheet 2 Patented Nov. 6, 1928.

UNITED STATES vPATENT oFFlcE.

THOMAS BATKOWSKI, OF CHICAGO HEIGHTS, ILLINOIS, ASSIGNOR T0 AMERICANMAN- i GANESE STEEL COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OFMAINE. y

BEPLACEABLE-POINT EXCAVATOB TOOTH.

Application led July 23, 1927. Serial No. 297,854.

cavator teeth have been designed with di-l vergent jaws on the pointhaving rearwardly extending clamping tangs, and with a nose on the baseadapted to enter between the jaws and recesses in the base extendingrearwardly from the nose and adapted to receive the clamping tangs. Inother instances, the point has been constructed in substantially theform of a `ferrule or pocket,

while the nose of the base has served as a shank to enter the pocket andto be there secured by wedges, bolts, or the like, passing through thewalls of the pocket and the intervening shank. It has also been thepractice to unite the jaws of the point by an integral web for thepurpose of tying them together and resisting spreading under thestresses whichthe point meets in use, the nose being slotted to receivethe tying web, and the jaws being in turn provided with overlapping lugsto embrace the members of.

the slotted nose to compensate for the weaknesses that would otherwiseresult from' their bifurcation. But in prior constructions, so far asthe same are known to me, there has not been cooperation between thelongitudinally remote points of 'articulation between the base and thepoint of a character that successfully resists relative motion betweenthe point and the base at such places of articulation, which isessential to the prevention of weaving or lost motion between the pointand the base, and essential to the prevention of excessive stresses uponthe articulating parts.

The obiect of the present invention is to so vimprove the bearing of theextreme forward end of the base in the point, as well as theconstruction through which the point receives said end, and the bearingof the ex- \-jaws at treme rear end of the point inthe base, as well asthe construction of the portion of the base which establishes saidbearing, in a manner to produce an improved articulation of the membersat the extremes of their overlapping or meeting portions, and establisharticulations which coact one with the other in a manner to render themmutually sustaining and therefore cause each to largely relievedestructive stresses that would otherwise be imposed upon the other. Theobject of the invention is, further, to so coordinate the constructionof the meeting portions of the point and base, at places intermediate oftheir extreme ends, that lost motion between the parts or weaving of thepoint upon the base, will be still further resisted and the end portionsof the articulations will be adapted to function still more eEectively.y

rlhe invention proceeds upon the principle of constructing the pointwith not only divergent jaws from which extend rearwardly, clampingtangs of the kind heretofore used, but tying the sides thereof insteadof at an intermediate plane, and which webs converge forwardly as do thedivergent jaws so that the webs and jaws together provide the four,sides of a tapering pocket, and the rearward- /ly presented faces ofthe webs afford abutment surfaces through which the point is received bythe base; and the base is provided not only with theknown feature ofupper and lower recesses which receive the clamping tangs of the point,with the longitudinal extension of the base between them, but has at theforward end of said extension a pyramidal nose, tapered vertically andlaterally, which Vlits in the tapered pocket of the point, while therear ends of the upper and lower recesses terminate in undercut seatsfor the abutment of the rear ends of the clamping tangs, and theseundercut seats are specially designed, for instance, by making them ofV-shaped section, to embrace the correspondingly designed rear ends ofthe tangs and force the latter inwardly in opposition to any spreadingtendency; and, finally, the base includes in its construction cheeksintegral with the forward extension of the base at the sides thereofproviding the lateral confines of the tang-rebeiving recesses, betweenwhich the webs which integrally unite the tangs snugly fit, and at thesame time providing vertica ly deep stiffening webs for said extensionand terminating at their forward ends in abutments substantiallyperpendicular to the axis of assembly which receive the rearwardlypresented abutting faces of the webs on the point. The result of thisco-mbination of fea-tures is to cause the point,

' when drawn firmly rearward by a wedging bolt of known construction, toenter into firm rearward bearing at the end of each clamping tang andalso through the vertical transverse faces of the cheeks and pointwebsand vertical and lateral bearing of the walls o-f the tapered pocketagainst the surfaces ofthe pyramidal nose, with the result that all lostmotion under vertical or horizontal transverse stresses is eliminated,vertical tipping stresses are converted almost wholly into shearstresses upon the wedging bolt; and lateral stresses, by reason of theclose lateral fit of the clamping tangs at the rear extremity and thefit of the nose in the pocket at the forward extremity, are taken up bythe cheeks and the webs of the point.

In the accompanying drawings- Figure 1 is a side elevation of a toothconstructed in accordance with the present invention, together with aportion of the lip of a dipper in section, the rear end of the base ofthe tooth, which will be of ordinary construction, being omitted.

Figure 2 is a section on the line 2"- of,

Figure 1.

Figure 3 is a section on the line 3"--3x of Figure 2; and

Figure 4 is a section on the line lx- 4x of Figures 1 and 3.

1 represents the lip of an excavating implement, for instance, a dipper,2 the base of a tooth mountedupon said lip, and the separately formedtip or point of the tooth replaceably (and preferably, also, reversibly)mounted on said base. The point is co-nstructed with jaws 4 havingforwardly and vertically converging inner faces 4a; webs 5 integral withsaid jaws at the sides thereof tying the jaws together and having theirinner surfaces 5 converging laterally in the forward direction andforming with the vertically converging jaw-surfaces 4 a tapered ferruleor pocket 1%a see Fig. 4); and clamping tangs 6 extending rearwardlyfrom the jaws 4, substantially parallel with the axis of assembly anddisassembly of the point, which tangs have openings 6a to receive aclamping bolt- 7 and terminate rearwardly in specially designed abutmentends 8, for instance, ends of V-shaped section.

The base 2 is constructed with upper and lower recesses 9 that receivethe tangs 6, leaving a forward longitudinal extension 10 between them,which is embraced by said tangs when in assembly; a pyramidal nose 11p-rojecting forwardly from the extension 10 and fitting the socket 3a ofthe point; and vertically deep cheeks 12 integral withthe extension 10at the sides thereof, forming the lateral confines of the recesses 9between which the tangsA 6 snugly fit laterally, as shown in Figure 2;said cheeks terminating forwardly in abutment faces 12 substantiallyperpendicular to the axis of assembly, preferably in the plane of mergerbetween the pyra-midal nose 11 and the extension 10, and receiving inlongitudinal abutment the rearwardly presented faces 5b of the webs 5.Recesses 9 termina-te rearwardly in undercut seats 13 designed toconform with the abutting ends 8 of the tangs 6 and serving the functionof sustaining the rear ends of the tangs not only longitudinally buttransversely so that they automatically assume a firm and immovableseating under longitudinal pressure of the tooth and are pressedinwardly upon the bottoms of the recesses 9 or vertically presentedsurfaces of the extension 10. Clamping bolt 7, as is usual, passesthrough a bore 14 in the base of the tooth, in the present instancethrough extension 10, and bears against the forward wall of the bore 14,and the rearward walls of the openings 6a in the tangs, with the resultthat the tanfs 6 in the undercut 13, and the socket 3 on the pyramidalnose 11, are drawn into firm seating.

With parts constructed as above described, it will be seen that whilevertical transverse stresses upon the point 3 tend to swing the pointabout one of the bearing ends 8 of a tang 6, as a fulcrum, such stressesare opposed by shearing resistance of the bolt 7 and by a direct bearingof a,face 4 of the socket 3 against a vertical wedging face 11a of thenose 11, and these last-named faces are at such large angles to the arcof tipping movement of that portion of the point, when a rear end of atang is acting as a fulcrum, that spreading stress upon the tang otherthan that whlch is acting as a. fulcrum is very slight; moreover, suchspreading stress is resisted by the hold-down face 13. When lateralstresses are imposed upo'n the point, they are opposed somewhat byshearing resistance of the bolt 7 due to the relatively large horizontaldimension of the seating faces 8 and 13; also by the snug fit of thetangs 6 between the lateral confines 12 of the recesses 9, but mainly bythe faces 11b of the nose in bearing against the laterally convergingfaces 5Ka of the point, at one end vof the articulation in coaction withthe snug-fit of the tangs, laterally, in the recesses at the other endof the articulation.

The construction herein described provides an articulation of the pointwith the base, which is made very firm in all transverse directions bymeans of bearing surfaces which are largely at the extremes of thelongitudinal dimension of articulation, with the result that weaving orlost motion of the point, on the base, and consequent excessivelocalizing of stresses, so destructive to ordinary point mountings, aresubstantially eliminated.

I claim:

1. A replaceable point excavator tooth, comprising a base and a pointadapted to be assembled with and disassembled from the basevsubstantially in the direction of the longitudinal axis of the tooth;said point being constructed with a pair of divergent` jawsand withintegral lateral Webs uniting said jaws and forming therewith anosereeeiving pocket, and with longitudinall extending clamping tangsterminatin in aseabutting ends rearwardly remote rom said pocket saidbase comprising upper and lower tang-receiving recesses leaving avertically reduced longitudinal base extension between them, andterminating at their rear ends in tang-receiving undercuts having faceswith which the tan s abut, inclined in the direction tovpress t e t-angstoward the bottoms of the recesses, means being provided for forcing thetangs rearwardly u on the base, cheeks on the base confining t e tangslaterally and terminating forwardly in abutments positioned to receivethev webs of the point, and a nose projecting from the base extensionbeyond the abutments of the cheeks and entering the pocket of thepoint.c

2. A replaceable point excavator tooth, comprising a base and a pointadapted to be assembled with the base substantially in the direction ofthe longitudinal axis of the tooth; the base being constructed withupper and lower tang-receiving recesses, approximately parallel withsald axis, leaving between them a vertically reduced longitudinallyextending body portion and terminating rearwardly in V-sliaped undercuttang abutments, vertically deep cheeks inte rral with said baseextension, forming latera confines of said recesses and terminating inforwardly presented web-receiving abutments, and a vertically andlaterally wedging nose integral with said longitudinal extension,rojecting beyond said cheeks; and the point bein constructed with a pairof jaws2 tying we s integral with and uniting said ]aws at the sidesthereof, said jaws and webs converging forwardly in conformity with thevertical and lateral wedging of the nose, said webs on the point and webreceiving abutments on the cheeks meeting continuously a dist-ancecorresponding to the vertical dimension of the extension and nose in aplane substantially perpendicular to the axis of assembl clampmg tangsextending rearwardly rom the jaws of the point, embracing the forwardextension of the face, fitting the recesses laterally, and conforming attheir inner ends to the V-shaped abutments, and means for drawing saidtangs in the direction of assembly and clamping them to the base.

Signed at Chicago Heights, Ill., this th day of July, 1927.

THOMAS RA'vrKoWsKI.

